matplotlib
diff --git a/‎lib/matplotlib/figure.py
Lines changed: 4 additions & 4 deletions b/‎lib/matplotlib/figure.py
Lines changed: 4 additions & 4 deletions
diff --git a/‎lib/matplotlib/tight_layout.py
Lines changed: 33 additions & 14 deletions b/‎lib/matplotlib/tight_layout.py
Lines changed: 33 additions & 14 deletions
@@ -1422,17 +1422,17 @@ def tight_layout(self, renderer=None, pad=1.08, h_pad=None, w_pad=None, rect=Non
             labels) will fit into. Default is (0, 0, 1, 1).
         """
 
-        from tight_layout import get_renderer, get_tight_layout_figure
+        from tight_layout import get_renderer, get_tight_layout_figure, \
+             get_subplotspec_list
 
-        subplot_axes = [ax for ax in self.axes if isinstance(ax, SubplotBase)]
-        if len(subplot_axes) < len(self.axes):
+        if None in get_subplotspec_list(self.axes):
             warnings.warn("tight_layout can only process Axes that descend "
                           "from SubplotBase; results might be incorrect.")
 
         if renderer is None:
             renderer = get_renderer(self)
 
-        kwargs = get_tight_layout_figure(self, subplot_axes, renderer,
+        kwargs = get_tight_layout_figure(self, self.axes, renderer,
                                          pad=pad, h_pad=h_pad, w_pad=w_pad,
                                          rect=rect)
 
 
@@ -209,6 +209,33 @@ def get_renderer(fig):
     return renderer
 
 
+def get_subplotspec_list(axes_list):
+    """
+    Return a list of subplotspec from the given list of axes.  For an
+    instance of axes that does not support subplotspec, None is
+    inserted in the list.
+
+    """
+    subplotspec_list = []
+    for ax in axes_list:
+        locator = ax.get_axes_locator()
+        if hasattr(locator, "get_subplotspec"):
+            subplotspec = locator.get_subplotspec().get_topmost_subplotspec()
+        elif hasattr(ax, "get_subplotspec"):
+            subplotspec = ax.get_subplotspec().get_topmost_subplotspec()
+        else:
+            subplotspec = None
+
+        if subplotspec is not None and \
+               subplotspec.get_gridspec().locally_modified_subplot_params():
+
+            subplotspec = None
+
+        subplotspec_list.append(subplotspec)
+
+    return subplotspec_list
+
+
 def get_tight_layout_figure(fig, axes_list, renderer,
                             pad=1.08, h_pad=None, w_pad=None, rect=None):
     """
@@ -244,21 +271,13 @@ def get_tight_layout_figure(fig, axes_list, renderer,
     ncols_list = []
     ax_bbox_list = []
 
-    subplot_dict = {} # for axes_grid1, multiple axes can share
-                      # same subplot_interface. Thus we need to
-                      # join them together.
-
-    for ax in axes_list:
-        locator = ax.get_axes_locator()
-        if hasattr(locator, "get_subplotspec"):
-            subplotspec = locator.get_subplotspec().get_topmost_subplotspec()
-        elif hasattr(ax, "get_subplotspec"):
-            subplotspec = ax.get_subplotspec().get_topmost_subplotspec()
-        else:
-            continue
+    subplot_dict = {} # multiple axes can share
+                      # same subplot_interface (e.g, axes_grid1). Thus
+                      # we need to join them together.
 
-        if (subplotspec is None) or \
-               subplotspec.get_gridspec().locally_modified_subplot_params():
+    for ax, subplotspec in zip(axes_list,
+                               get_subplotspec_list(axes_list)):
+        if subplotspec is None:
             continue
 
         subplots = subplot_dict.setdefault(subplotspec, [])